DE739887C
Expired / Lapsed
DE
⏱️ 0.0 years remaining
Additional contact device on desktop telephones for triggering a busy signal
Assignee: RICHARD KATZMAYR DIPL ING
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Filing: 1940-09-03
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Granted: 1943-10-07
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Expires: 1960-09-03
Abstract
No abstract record available.
Inventors
- 👤 Dipl-Ing Richard Katzmayr
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-11-05 22:19
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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